Numerous types of pressure responsive switching mechanisms or devices are known in the prior art. One type of switching device utilizes a pair of magnets to cause the motion of an actuator arm of an electrical switch. One of the magnets is carried by a leaf spring and is disposed in a chamber bounded on one side by a solid wall of casing and on another side by a flexible diaphragm. The motion of the flexible diaphragm moves the first magnet toward the wall of the casing. The second magnet is disposed in the casing adjacent the above-mentioned wall. The two magnets are arranged such that their like poles are directly opposite one another. The motion of the first magnet toward the wall of the casing thus repels the second magnet and activates the actuator arm of the electrical switch. Such a switch mechanism is shown in United States Woolford Pat. No. 3,368,173. A similar system is shown in United States Wolford Pat. No. 3,349,203.
Another type of pressure-actuated switch utilizes a solid plate member as a pressure reactive surface. The plate is spring biased in one direction and is movable against the bias of one or more springs when pressure is applied to the plate. One or more mechanical linkage mechanisms or rods couple the plate to one or more electrical switches. Such switch mechanisms are disclosed in United States Weber Pat. Nos. 3,786,212 and 3,898,405. A mechanical switching mechanism of the type discussed above is also produced by the Automatic Switch Co. of Florham Park, N.J.